brute fact

The rationalist, Kantian definition of truth, therefore, fails. At the bottom of every fact there is an act of reason, and thus no realist notion of truth serves; at the bottom of every rational necessity there is a choice, the act of invention, and so no critical definition of truth serves.³ ² ⁹ The forms and categories of thought themselves need verification in an experience which does not apply them so much as make them.³ ³ ⁰ That the very conditions of intelligibility change and develope is clear, according to LR, from the history of science.³ ³ ¹ Further, a list of categories given once and for all is nothing but itself a brute fact, an irrational surd, if it cannot itself be explained.³ ³ ²